Boring and cutting tool



G. G. PORTER.

BORING AND CUTTING TOOL.

APPLICATION FILED was 11, 1919.

v Patented m. 23, 1920.

IN VEN TOR.

2 Q s \V w, a T/ o 'Arromvsys eras VP TENT FF CE;

(mouse a. roman, or'sYRnoUsE, NEW; YORK.

BORING AND QU'ITINGZTVOOL.

Application filed June 17, 1919. SerialNo. 304,866.

To all whom it may concern:

Be it known that I, GEORGE Gr. Pon'rnn, a citizen of the United States, and a resident of Syracuse, in the county of Onondaga and State of New York, have invented a certain new and useful Boring and Cutting Tool, of which the following is a specification.

This invention relates to boring and cutting tools for use in lathes, boring mills, screw machines and other machine tools, and

has for its object a boring tool witha suitably formed cutting lip having proper cutting and clearance angles, and which can be re-sharpened by simply grinding it on its top face, without changing the shape ofthe cutting lip.

Another object is to provide a tool with Other objects are to provide a tool with properly formed cutting and clearance angles and cutting lip which can be sharpened much quicker and easier than the ordinary forms of boring tools and by a person or operator not highly skilled in the art, thereby effecting further savings.

In describing this invention, reference is had to the accompanying drawings in which like characters designate corresponding parts in all the views.

'Figure 1 is an elevation, shown partly in section of one form of boring tool in which the cutter head is made of expensive high speed or carbon tool steel, and is detachably secured to a shank of low grade steel.

Fig. 2 is an elevation of the tool look ing upwardly in Fig. 1.

Fig. 3 is an end view thereof, a circle indicating the position of a hole being bored with reference to the cutting lip also shown.

Figs. l, 5 and 6 are views similar to Figs' 1, 2 and 3, of another form of boring tool in which the cutter head is integral with or integrally united to the shank. I

This tool comprises a cutter having a long helical cutting lip so formed around the axis of the tool that it can be repeatedly sharpened by merely grinding the top thereof so be small.

that the entire cutter which is composed of expensive tool steel can be almost entirely used and no useless stub of tool steel is left. Furthermore, the cuttercan be sharpened quickly without the exercise of a high degree of skill thereby effecting a considerable saving in time.

This tool is formed with a peripheral blade or lip extending around the same and terminating in an end edge face facing in a direction toward the longitudinal plane the cutter.

The outer faces,

lateral side facesfof the blade meeting the end edge face to formfthe'cutting edges.-

- The cutter 1' is formed with a helical blade or lip 2 having a plurality of convolutions which gradually increase in diameter toward the outer end of the cutter and the outer and larger end convolution terminates in Specification of Letters Patent. {Patented N V. 23, 1920.

that is the peripheral and I an end edge ortopface 3 facing toward the longitudinal plane of the cutter, said face 3 being located below the center of the cuttcr out of a plane radial with the axis of the cutter thereby providing maximum clearance for the cutting edge asseen in Fig. 3. v If the face were on the center or radial, or above the center, the clearance would By below center, is meant that the convolution is ground down beyond or past the center instead of providing said face on a portion containing or extending over the center. gradually increasing in diameter, clearance Gwing to the convolutions;

is provided for the convolutions so that they will not touch the sides of the hole being bored, it being understood that the tool is.

located with its axis parallel to the axis of the hole.

1 is the shank of the tool made of a cheaper grade of steel, and as seen in Figs. 1 and 2 the cutter is detachably mounted on the shank. This permits of the same shank being used for different cutterswhich might be formed with different clearance angles and ground with different amounts of rake on the top to suit the required cutting conditions of the work to be done and the ideas of the operator. Also the same shank can be used repeatedly for other outters as they become worn out.

As illustrated in Figs, 1 and 2, the cutter is formed with an axially threaded bore and the shank 1 is tubular, and theparts 1 and 4. are secured together by a fastening memher as a screw 5 extending lengthwise of and within the tubular shank l and threading into the bore of the'cutter 1. The head 6 of thescrew bears against the outer end of the shank, also, the meeting faces of the cutter 1 and shank 4: are here shown as formedwith interlocking teeth or jaws 7 which take all of the twisting strain and prevent the cutter from shifting on the shank, the bolt being depended on only for holding the cutter against the face of the shank.

In Figs. 41-. and 5, the cutter 8 is shown as formed integral with or integrally united to the shank.

In Figs. 1 and, 4:, the blade is shown as formed with a conical periphery.

Qwing to the receding of the peripheries of the convolutions of the blades, all that is necessary in sharpening the cutter is to grind off the top edge face 3, and owing to the convolutions a long lip can be provided the entire length of the helical portion of the cutter'formed of tool steel so that the life of the cutter is comparatively long and further the part of the cutter composed of expensive tool steel can be almost entirely consumed.

hat I claim is: V

1. A cutting tool having a helical cutting lip terminating at the endof the tool in an end edge face facing toward the longitudinal plane of the tool and below the center out crease in diameter toward the free end of the tool, the end convolution terminating in an end edge face facing in a direction toward the longitudinal plane of the tool, substantially as and for the purpose specified.

8. A boring tool having atubular shank, a cutter head arranged end to end with the shank, the shank and head having interlocking teeth on their abutting ends and a fastening member extending through the tubu lar shank and into the cutter head, substantially as and for the purpose specified.

4. A metal cutting tool comprising a shank, a cutter mounted on'the end of the shank and having a helical cutting lip terminating at the end. of the tool in'an end edge face, said shank being tubular and the cutter having a threaded bore alined with a passage of the shank, and ascrew extending lengthwise of the tubular shank and ex- I tending into the bore of the cutter, substantially as and for the purpose specified.

In testimony whereof, I have hereunto signed my name, at. Syracuse,,in the county of Onondaga, and State of New York, this 14th day of May, 1919.

GEORGE G. PORTER. 

